// SPDX-License-Identifier: GPL-2.0 or MIT
/*
* Copyright 2018 Noralf Trønnes
*/
#include <linux/iosys-map.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <drm/drm_client.h>
#include <drm/drm_debugfs.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem.h>
#include <drm/drm_mode.h>
#include <drm/drm_print.h>
#include "drm_crtc_internal.h"
#include "drm_internal.h"
/**
* DOC: overview
*
* This library provides support for clients running in the kernel like fbdev and bootsplash.
*
* GEM drivers which provide a GEM based dumb buffer with a virtual address are supported.
*/
static int drm_client_open(struct drm_client_dev *client)
{
struct drm_device *dev = client->dev;
struct drm_file *file;
file = drm_file_alloc(dev->primary);
if (IS_ERR(file))
return PTR_ERR(file);
mutex_lock(&dev->filelist_mutex);
list_add(&file->lhead, &dev->filelist_internal);
mutex_unlock(&dev->filelist_mutex);
client->file = file;
return 0;
}
static void drm_client_close(struct drm_client_dev *client)
{
struct drm_device *dev = client->dev;
mutex_lock(&dev->filelist_mutex);
list_del(&client->file->lhead);
mutex_unlock(&dev->filelist_mutex);
drm_file_free(client->file);
}
/**
* drm_client_init - Initialise a DRM client
* @dev: DRM device
* @client: DRM client
* @name: Client name
* @funcs: DRM client functions (optional)
*
* This initialises the client and opens a &drm_file.
* Use drm_client_register() to complete the process.
* The caller needs to hold a reference on @dev before calling this function.
* The client is freed when the &drm_device is unregistered. See drm_client_release().
*
* Returns:
* Zero on success or negative error code on failure.
*/
int drm_client_init(struct drm_device *dev, struct drm_client_dev *client,
const char *name, const struct drm_client_funcs *funcs)
{
int ret;
if (!drm_core_check_feature(dev, DRIVER_MODESET) || !dev->driver->dumb_create)
return -EOPNOTSUPP;
client->dev = dev;
client->name = name;
client->funcs = funcs;
ret = drm_client_modeset_create(client);
if (ret)
return ret;
ret = drm_client_open(client);
if (ret)
goto err_free;
drm_dev_get(dev);
return 0;
err_free:
drm_client_modeset_free(client);
return ret;
}
EXPORT_SYMBOL(drm_client_init);
/**
* drm_client_register - Register client
* @client: DRM client
*
* Add the client to the &drm_device client list to activate its callbacks.
* @client must be initialized by a call to drm_client_init(). After
* drm_client_register() it is no longer permissible to call drm_client_release()
* directly (outside the unregister callback), instead cleanup will happen
* automatically on driver unload.
*
* Registering a client generates a hotplug event that allows the client
* to set up its display from pre-existing outputs. The client must have
* initialized its state to able to handle the hotplug event successfully.
*/
void drm_client_register(struct drm_client_dev *client)
{
struct drm_device *dev = client->dev;
int ret;
mutex_lock(&dev->clientlist_mutex);
list_add(&client->list, &dev->clientlist);
if (client->funcs && client->funcs->hotplug) {
/*
* Perform an initial hotplug event to pick up the
* display configuration for the client. This step
* has to be performed *after* registering the client
* in the list of clients, or a concurrent hotplug
* event might be lost; leaving the display off.
*
* Hold the clientlist_mutex as for a regular hotplug
* event.
*/
ret = client->funcs->hotplug(client);
if (ret)
drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
}
mutex_unlock(&dev->clientlist_mutex);
}
EXPORT_SYMBOL(drm_client_register);
/**
* drm_client_release - Release DRM client resources
* @client: DRM client
*
* Releases resources by closing the &drm_file that was opened by drm_client_init().
* It is called automatically if the &drm_client_funcs.unregister callback is _not_ set.
*
* This function should only be called from the unregister callback. An exception
* is fbdev which cannot free the buffer if userspace has open file descriptors.
*
* Note:
* Clients cannot initiate a release by themselves. This is done to keep the code simple.
* The driver has to be unloaded before the client can be unloaded.
*/
void drm_client_release(struct drm_client_dev *client)
{
struct drm_device *dev = client->dev;
drm_dbg_kms(dev, "%s\n", client->name);
drm_client_modeset_free(client);
drm_client_close(client);
drm_dev_put(dev);
}
EXPORT_SYMBOL(drm_client_release);
/**
* drm_client_dev_unregister - Unregister clients
* @dev: DRM device
*
* This function releases all clients by calling each client's
* &drm_client_funcs.unregister callback. The callback function
* is responsibe for releaseing all resources including the client
* itself.
*
* The helper drm_dev_unregister() calls this function. Drivers
* that use it don't need to call this function themselves.
*/
void drm_client_dev_unregister(struct drm_device *dev)
{
struct drm_client_dev *client, *tmp;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return;
mutex_lock(&dev->clientlist_mutex);
list_for_each_entry_safe(client, tmp, &dev->clientlist, list) {
list_del(&client->list);
if (client->funcs && client->funcs->unregister) {
client->funcs->unregister(client);
} else {
drm_client_release(client);
kfree(client);
}
}
mutex_unlock(&dev->clientlist_mutex);
}
EXPORT_SYMBOL(drm_client_dev_unregister);
/**
* drm_client_dev_hotplug - Send hotplug event to clients
* @dev: DRM device
*
* This function calls the &drm_client_funcs.hotplug callback on the attached clients.
*
* drm_kms_helper_hotplug_event() calls this function, so drivers that use it
* don't need to call this function themselves.
*/
void drm_client_dev_hotplug(struct drm_device *dev)
{
struct drm_client_dev *client;
int ret;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return;
if (!dev->mode_config.num_connector) {
drm_dbg_kms(dev, "No connectors found, will not send hotplug events!\n");
return;
}
mutex_lock(&dev->clientlist_mutex);
list_for_each_entry(client, &dev->clientlist, list) {
if (!client->funcs || !client->funcs->hotplug)
continue;
if (client->hotplug_failed)
continue;
ret = client->funcs->hotplug(client);
drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);
if (ret)
client->hotplug_failed = true;
}
mutex_unlock(&dev->clientlist_mutex);
}
EXPORT_SYMBOL(drm_client_dev_hotplug);
void drm_client_dev_restore(struct drm_device *dev)
{
struct drm_client_dev *client;
int ret;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return;
mutex_lock(&dev->clientlist_mutex);
list_for_each_entry(client, &dev->clientlist, list) {
if (!client->funcs || !client->funcs->restore)
continue;
ret = client->funcs->restore(client);
drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);
if (!ret) /* The first one to return zero gets the privilege to restore */
break;
}
mutex_unlock(&dev->clientlist_mutex);
}
static void drm_client_buffer_delete(struct drm_client_buffer *buffer)
{
if (buffer->gem) {
drm_gem_vunmap_unlocked(buffer->gem, &buffer->map);
drm_gem_object_put(buffer->gem);
}
kfree(buffer);
}
static struct drm_client_buffer *
drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height,
u32 format, u32 *handle)
{
const struct drm_format_info *info = drm_format_info(format);
struct drm_mode_create_dumb dumb_args = { };
struct drm_device *dev = client->dev;
struct drm_client_buffer *buffer;
struct drm_gem_object *obj;
int ret;
buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
if (!buffer)
return ERR_PTR(-ENOMEM);
buffer->client = client;
dumb_args.width = width;
dumb_args.height = height;
dumb_args.bpp = drm_format_info_bpp(info, 0);
ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
if (ret)
goto err_delete;
obj = drm_gem_object_lookup(client->file, dumb_args.handle);
if (!obj) {
ret = -ENOENT;
goto err_delete;
}
buffer->pitch = dumb_args.pitch;
buffer->gem = obj;
*handle = dumb_args.handle;
return buffer;
err_delete:
drm_client_buffer_delete(buffer);
return ERR_PTR(ret);
}
/**
* drm_client_buffer_vmap_local - Map DRM client buffer into address space
* @buffer: DRM client buffer
* @map_copy: Returns the mapped memory's address
*
* This function maps a client buffer into kernel address space. If the
* buffer is already mapped, it returns the existing mapping's address.
*
* Client buffer mappings are not ref'counted. Each call to
* drm_client_buffer_vmap_local() should be closely followed by a call to
* drm_client_buffer_vunmap_local(). See drm_client_buffer_vmap() for
* long-term mappings.
*
* The returned address is a copy of the internal value. In contrast to
* other vmap interfaces, you don't need it for the client's vunmap
* function. So you can modify it at will during blit and draw operations.
*
* Returns:
* 0 on success, or a negative errno code otherwise.
*/
int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,
struct iosys_map *map_copy)
{
struct drm_gem_object *gem = buffer->gem;
struct iosys_map *map = &buffer->map;
int ret;
drm_gem_lock(gem);
ret = drm_gem_vmap(gem, map);
if (ret)
goto err_drm_gem_vmap_unlocked;
*map_copy = *map;
return 0;
err_drm_gem_vmap_unlocked:
drm_gem_unlock(gem);
return ret;
}
EXPORT_SYMBOL(drm_client_buffer_vmap_local);
/**
* drm_client_buffer_vunmap_local - Unmap DRM client buffer
* @buffer: DRM client buffer
*
* This function removes a client buffer's memory mapping established
* with drm_client_buffer_vunmap_local(). Calling this function is only
* required by clients that manage their buffer mappings by themselves.
*/
void drm_client_buffer_vunmap_local(struct drm_client_buffer *buffer)
{
struct drm_gem_object *gem = buffer->gem;
struct iosys_map *map = &buffer->map;
drm_gem_vunmap(gem, map);
drm_gem_unlock(gem);
}
EXPORT_SYMBOL(drm_client_buffer_vunmap_local);
/**
* drm_client_buffer_vmap - Map DRM client buffer into address space
* @buffer: DRM client buffer
* @map_copy: Returns the mapped memory's address
*
* This function maps a client buffer into kernel address space. If the
* buffer is already mapped, it returns the existing mapping's address.
*
* Client buffer mappings are not ref'counted. Each call to
* drm_client_buffer_vmap() should be followed by a call to
* drm_client_buffer_vunmap(); or the client buffer should be mapped
* throughout its lifetime.
*
* The returned address is a copy of the internal value. In contrast to
* other vmap interfaces, you don't need it for the client's vunmap
* function. So you can modify it at will during blit and draw operations.
*
* Returns:
* 0 on success, or a negative errno code otherwise.
*/
int
drm_client_buffer_vmap(struct drm_client_buffer *buffer,
struct iosys_map *map_copy)
{
struct drm_gem_object *gem = buffer->gem;
struct iosys_map *map = &buffer->map;
int ret;
drm_gem_lock(gem);
ret = drm_gem_pin_locked(gem);
if (ret)
goto err_drm_gem_pin_locked;
ret = drm_gem_vmap(gem, map);
if (ret)
goto err_drm_gem_vmap;
drm_gem_unlock(gem);
*map_copy = *map;
return 0;
err_drm_gem_vmap:
drm_gem_unpin_locked(buffer->gem);
err_drm_gem_pin_locked:
drm_gem_unlock(gem);
return ret;
}
EXPORT_SYMBOL(drm_client_buffer_vmap);
/**
* drm_client_buffer_vunmap - Unmap DRM client buffer
* @buffer: DRM client buffer
*
* This function removes a client buffer's memory mapping. Calling this
* function is only required by clients that manage their buffer mappings
* by themselves.
*/
void drm_client_buffer_vunmap(struct drm_client_buffer *buffer)
{
struct drm_gem_object *gem = buffer->gem;
struct iosys_map *map = &buffer->map;
drm_gem_lock(gem);
drm_gem_vunmap(gem, map);
drm_gem_unpin_locked(gem);
drm_gem_unlock(gem);
}
EXPORT_SYMBOL(drm_client_buffer_vunmap);
static void drm_client_buffer_rmfb(struct drm_client_buffer *buffer)
{
int ret;
if (!buffer->fb)
return;
ret = drm_mode_rmfb(buffer->client->dev, buffer->fb->base.id, buffer->client->file);
if (ret)
drm_err(buffer->client->dev,
"Error removing FB:%u (%d)\n", buffer->fb->base.id, ret);
buffer->fb = NULL;
}
static int drm_client_buffer_addfb(struct drm_client_buffer *buffer,
u32 width, u32 height, u32 format,
u32 handle)
{
struct drm_client_dev *client = buffer->client;
struct drm_mode_fb_cmd2 fb_req = { };
int ret;
fb_req.width = width;
fb_req.height = height;
fb_req.pixel_format = format;
fb_req.handles[0] = handle;
fb_req.pitches[0] = buffer->pitch;
ret = drm_mode_addfb2(client->dev, &fb_req, client->file);
if (ret)
return ret;
buffer->fb = drm_framebuffer_lookup(client->dev, buffer->client->file, fb_req.fb_id);
if (WARN_ON(!buffer->fb))
return -ENOENT;
/* drop the reference we picked up in framebuffer lookup */
drm_framebuffer_put(buffer->fb);
strscpy(buffer->fb->comm, client->name, TASK_COMM_LEN);
return 0;
}
/**
* drm_client_framebuffer_create - Create a client framebuffer
* @client: DRM client
* @width: Framebuffer width
* @height: Framebuffer height
* @format: Buffer format
*
* This function creates a &drm_client_buffer which consists of a
* &drm_framebuffer backed by a dumb buffer.
* Call drm_client_framebuffer_delete() to free the buffer.
*
* Returns:
* Pointer to a client buffer or an error pointer on failure.
*/
struct drm_client_buffer *
drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format)
{
struct drm_client_buffer *buffer;
u32 handle;
int ret;
buffer = drm_client_buffer_create(client, width, height, format,
&handle);
if (IS_ERR(buffer))
return buffer;
ret = drm_client_buffer_addfb(buffer, width, height, format, handle);
/*
* The handle is only needed for creating the framebuffer, destroy it
* again to solve a circular dependency should anybody export the GEM
* object as DMA-buf. The framebuffer and our buffer structure are still
* holding references to the GEM object to prevent its destruction.
*/
drm_mode_destroy_dumb(client->dev, handle, client->file);
if (ret) {
drm_client_buffer_delete(buffer);
return ERR_PTR(ret);
}
return buffer;
}
EXPORT_SYMBOL(drm_client_framebuffer_create);
/**
* drm_client_framebuffer_delete - Delete a client framebuffer
* @buffer: DRM client buffer (can be NULL)
*/
void drm_client_framebuffer_delete(struct drm_client_buffer *buffer)
{
if (!buffer)
return;
drm_client_buffer_rmfb(buffer);
drm_client_buffer_delete(buffer);
}
EXPORT_SYMBOL(drm_client_framebuffer_delete);
/**
* drm_client_framebuffer_flush - Manually flush client framebuffer
* @buffer: DRM client buffer (can be NULL)
* @rect: Damage rectangle (if NULL flushes all)
*
* This calls &drm_framebuffer_funcs->dirty (if present) to flush buffer changes
* for drivers that need it.
*
* Returns:
* Zero on success or negative error code on failure.
*/
int drm_client_framebuffer_flush(struct drm_client_buffer *buffer, struct drm_rect *rect)
{
if (!buffer || !buffer->fb || !buffer->fb->funcs->dirty)
return 0;
if (rect) {
struct drm_clip_rect clip = {
.x1 = rect->x1,
.y1 = rect->y1,
.x2 = rect->x2,
.y2 = rect->y2,
};
return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,
0, 0, &clip, 1);
}
return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,
0, 0, NULL, 0);
}
EXPORT_SYMBOL(drm_client_framebuffer_flush);
#ifdef CONFIG_DEBUG_FS
static int drm_client_debugfs_internal_clients(struct seq_file *m, void *data)
{
struct drm_debugfs_entry *entry = m->private;
struct drm_device *dev = entry->dev;
struct drm_printer p = drm_seq_file_printer(m);
struct drm_client_dev *client;
mutex_lock(&dev->clientlist_mutex);
list_for_each_entry(client, &dev->clientlist, list)
drm_printf(&p, "%s\n", client->name);
mutex_unlock(&dev->clientlist_mutex);
return 0;
}
static const struct drm_debugfs_info drm_client_debugfs_list[] = {
{ "internal_clients", drm_client_debugfs_internal_clients, 0 },
};
void drm_client_debugfs_init(struct drm_device *dev)
{
drm_debugfs_add_files(dev, drm_client_debugfs_list,
ARRAY_SIZE(drm_client_debugfs_list));
}
#endif
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